Blanking plate for gas flow passages



Se t. 8, 1970 s. PRESSLAUER 3,527,440

BLANKING PLATE FOR GAS FLOW PASSAGES Filed June 17, 1968 4 Sheets-Sheet 1 E H i U J mi Q I F HCIIIIIIIZ'LZIIIIIIZII l & I Q f; '\i

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ATTORNEYS Sept. 8, 1970 s. PRESSLAUER 3,527,440

BLANKING PLATE FOR GAS FLOW PASSAGES Filed June 17, 1968 4 Sheets-Sheet 2 Q H. X

INVENTOR. SIEGFRIED PRESSLAUER BY ATTORNEYS p 1970 s. PRESSLAUER 3,527,440

BLANKING PLATE FOR GAS FLOW PASSAGES Filed June 17, 1968 4 Sheeis-Sheet 4 INVENTOR.

SIEGFRIED PRESSLAUER W ATTORNEYS United States Patent 3,527,440 BLANKING PLATE FOR GAS FLOW PASSAGES Siegfried Presslauer, Seekonk, Mass, assignor to Tower Iron Works Inc., Seekonk, Mass, a corporation of Rhode Island Filed June 17, 1968, Ser. No. 737,518 Int. Cl. F161: 3/10 U.S. Cl. 251-187 3 Claims ABSTRACT OF THE DISCLOSURE A blanking plate assembly for gas flow passages, such as turbine passages and the like, movable from a completely open position wherein the gas is free to flow through the passage to a heat exchanger, boiler or the like to a completely closed position wherein the gas-flow is completely blocked and diverted to permit complete and safe isolation of a heat exchanger, boiler or any other equipment located downstream from the blanking plate without shutting down the entire system.

Several problems have been encountered with prior arrangements for effecting close-off turbine passages and the like. For example, because of the size and weight of the blanking plate, difficulty in moving the plate was experienced; the plate would freeze in closed position; the plate would damage the seat during movement; and a tight peripheral seal Was not easily obtainable. Close tolerance manufacture of the blanking plate is expensive and does not solve the problem because of the high tempera ture of the gases in the passage which causes warping and uneven seating.

Accordingly, it is a primary object of the present invention to provide an improved blanking plate assembly for turbine passages and the like which overcomes problems heretofore encountered.

Another object of the present invention is to provide an improved blanking plate assembly for turbine passages and the like wherein a blanking plate of non-rigid design and wide tolerances can be utilized, yet wherein tight seating can be effected when in closed position.

A further object of the present invention is to provide an improved blanking plate assembly wherein novel means is employed for moving the blanking plate into and out of seating engagement with the passage it controls and for moving the blanking plate between open and closed positions.

Still another object of the present invention is to provide simple means for eflecting a tight peripheral seal throughout the circumference of the seat.

A still further object of the present invention is to provide an improved blanking plate assembly wherein a nonmetallic seat can be employed and wherein relative movement between the plate and passage is such that abrasive sliding contact against the seat is obviated.

Still another object of the present invention is to provide an improved blanking plate assembly wherein the blanking plate can be of lightweight construction.

A further object is the provision of a blanking plate that when in closed or blocking position permits complete and safe isolation of a heat exchanger, boiler or the like without shutting down the entire system.

Various other objects and advantages will become apparent from the detailed description to follow.

The blanking plate assembly of the instant invention comprises a plate adapted to be moved between closed and open positions suitable means such as a rack and pinion, with the plate supported on its back and front faces and bottom edge by rollers. Certain of the rollers ride on tracks which support the plate out of contact with its passage seat during lateral movement but allow it to move to seating position when laterally moved to fully closed position. Bolts are provided around the periphery to constitute multiple pressure points for clamping the plate in seating positions. Also a series of bolts are provided for unseating the plate. The plate is of relatively non-rigid design so that it can be conformed to the contour of the seating against which it is pressed.

In the drawings:

FIG. 1 is a top plan view of a turbine passage with the blanking plate assembly of the present invention incorporated therein;

FIG. 2 is an enlarged detail plan view of the blanking plate assembly and operating means, per se;

FIG. 3 is a side elevational view of the assembly; and

FIG. 4 is a vertical sectional view taken substantially on the plane of line 44 in FIG. 3.

Although my invention is applicable to any system having a gas flow passage, it has been illustrated and will be described in connection with a turbine system wherein the gases flow to a heat exchanger, boiler or the like. It will be understood, however, that this represents only one of many environments in which my invention has utility.

Referring more particularly to the drawings wherein like numerals apply to like parts throughout, it will be seen that I have provided an improved blanking plate assembly 10 for a turbine passage 12 in a turbine system 14. Details of the turbine system are well known in the art so it will suflice to say that 12 is the passage from the turbine, with the gas flow in the direction of arrow 16, to the heat exchanger 18. The blanking plate assem bly 10 is interposed in passage 12 so that the gas flow can be diverted into the passage 20 past dampers at 22 when it is desired to do repair work in the heat exchanger without shutting down the entire system.

The passage has end faces 24 and 26 between which the blanking plate assembly is to be received and secured, as by bolts.

Referring to FIGS. 3 and 4, the details of the assembly will now be described.

The casing or housing for the assembly comprises a pair of channels 28, 30 across the top and a pair of channels 32, 34 across the bottom with similar vertical channels 36 and 38 at the sides joined as by weld or other suitable means. The channels 28, 30, 32, 34, 36 and 38 define the passageway corresponding with the turbine passage to the heat economizer. The channels abut the flanges 40, 42 at their end faces 24, 26 for joinder therewith, as shown most clearly in FIG. I.

The channels are longitudinally spaced, i.e., the flanges 44, 46 are spaced from each other as are the flanges 48, 50: Side plate 52 is abutted against flanges 44, 48 and welded or otherwise secured thereto. Plate 52 is of a size to form a side panel of the box into which the blanking plate is to be retracted for its open position. The box shown generally at 54 also includes a second side plate 56 secured to channels 30, 34 and the respective side channels 36, 38, a top plate 58 and a bottom plate 60.

For strength, I provide an exterior frame for the box 54 including a series of vertical channels 62, and a series of horizontal channels 64 (not shown) joining the opposing vertical channels and opposing horizontal channels at the top and bottom and sides, respectively.

A suitable access door is provided at 66 closed as by bolts.

Around the passageway, the casing is rigidi-fied as by the plates 68, 70. Also the plate 52 has inturned walls at 72, 74 acting as baflles to prevent gas from flowing out of the duct passage toward walls 58, 60.

Another access door is provided at 76 secured as by bolts for access into the casing about the blanking plate.

The blanking plate is shown at 78 as being a large rectangular sheet of a size greater than the passageway 80.

It is relatively non-rigid but may be provided with reinforcing ribs for strength against the gas pressure. The plate 78 is supported on its lower edge 82 by a series of rollers 84 adapted to ride on bottom wall 60. One face of plate 78 has a series of upper and a series of lower rollers 86, 88 which are adapted to ride on tracks 90, 92 when in box 54. The tracks 90, 92 terminate at passage 80 so that the plate 78 can be moved to the right, when viewed in FIG. 4, and when in position to close passageway 80 as will be described.

Similarly a series of upper and a series of lower rollers 94, 96 are attached on the opposing side of plate 78 and similarly ride on tracks 98, 100. The tracks thus support the plate 78 as it moves through box 54 to its blocking position in passage '80. As the plate moves into passage 80 the tracks 90, 92 are no longer present but gas pressure in the passage holds the plate against tracks 98, 100. If no gas pressure is present, the plate will still be maintained against tracks 98, 100 due to the fact all of the rollers 86, 88 will not become disengaged from tracks 90, 92 until the plate 78 is completely in its blocking position in passage 80.

A seat in the form of a gasket 106 is secured on the seating face 108 of plate 78 for cooperation with the seating face 110 of the flanges 46, 50 and at the sides as well.

When the plate is in position to close passageway 80, it is free of the tracks 90 and 92, as aforesaid. The series of elements 112 in the form of bolts through wall 52 can be threaded against bosses 114 on the plate 78 to press the seating faces into interengagement so that seat 106 seals against seat 110 to close 01f the flow of gas through passage 80.

The element 116, also preferably bolts, are carried on side wall 56 and can be threaded inwardly to unseat plate when it is desired to retract plate 78 from its closed position. Of course, bolts 112 must first be retracted.

Any suitable means may be employed for moving the plate 78 between open and closed position. One such means includes rack 118, carried on bracket 120' secured to plate 78, and a pinion 122 engaged with the rack. Pinion 122 is mounted on shaft 124 which in turn is supported in bearings 126, 128 carried by frame 130 of any suitable design. A sprocket 132 is mounted on the outer end of shaft 124.

A drive mechanism, which can be electrically or handoperated, includes a box 134 with a drive shaft 136 extending therefrom. Shaft 136 has a sprocket 138 and a link belt 140 is engaged over the sprockets 132, 138 to drivingly connect the same. Box 134 is mounted on frame 140 and a hand wheel 142 may be utilized to drive sprocket 138 as by a bevel gear arrangement (not shown). Rigidifying angles 144, 146 are provided as shown in FIG. 2. Also, a protective casings is provided 148 for the link belt.

Thus plate 78 can be moved from box 54 to closed position and back to open position by operation of the hand wheel and through the rack and pinion arrangements. Other equivalent arrangements involving the use of a screw, pulley, or chain could also be used for effecting opening and closing of plate 78.

It will be understood that when the plate 78 is moved to closed position, the rollers first ride on the tracks 90', 92, 98, 100 and then are free of the tracks 90', 92 when the plate is in the passageway. The plate by reason of its non-rigid construction, can be clamped closed by the bolts 112 providing multiple pressure points whereby irregularity in the seats is overcome.

In view of the foregoing it is believed that I have provided an improved blanking plate assembly which fulfills the objects hereinbefore enumerated.

What is claimed is:

1. A blanking plate assembly for closing flow of gas through a gas flow passage, said assembly comprising a blanking plate slidably movable between two end positions, in one of which positions said passage is fully open and in the other of which positions said passage is closed, said plate being larger than said passage whereby when said plate is in its closed position it has a marginal portion that extends outwardly beyond the periphery of said passage, operating means connected with said plate for moving it betwen said end positions, said plate and passage having cooperating peripheral seat means, pressure means carried by said assembly for forcing said plate into and out of sealing-engagement with said passage when the plate is in its closed position whereby said seat means block flow of gas through said passage, roller means carried by said plate marginal portion on opposite sides thereof and at one pair of opposite edges thereof, and track means carried by said assembly for receiving said roller means, said roller means and track means cooperating to maintain said plate substantially normal to the longitudinal axis of said passage during slidable movement of said plate between its said end positions and at the same time maintaining said peripheral seat means disengaged during said movement, the track means adjacent the side of said plate opposite from the direction of gas flow extending completely across said passage, the track means adjacent the other side of the plate terminating short of the passage, whereby when the plate has moved to its blocking position, the plate is free to be moved into sealing engagement by said pressure means.

2. In the assembly of claim 1, said roller means comprising a series of aligned rollers extending across said plate at the aforesaid locations on said plate, the axes of said rollers being substantially parallel to the plane of said plate.

3. In the assembly of claim 2, the rollers on the side of the plate closest to the direction of gas flow being located closer to the peripheral edge of said marginal plate portion than the rollers on the opposite side thereof.

References Cited UNITED STATES PATENTS 1,475,731 11/1923 Windett 251-158 1,970,964 8/1934 Hosmer 251158 2,786,644 3/1957 Koppl 251187 3,170,668 2/1965 Aulisa 251-158 3,272,475 9/1966 Bryant 251203 FOREIGN PATENTS 630,742 6/ 1936 Germany.

HAROLD W. WEAKLEY, Primary Examiner U.S. Cl. X.R. 251-158, 193, 329 

